It is the purpose of this project to study the chemistry and structure of amyloid and amyloid related proteins. The main topics of present interest are: 1) Isolation and chemical characterization of amyloid fibril protein from various types of systemic amyloidosis and localized amyloid deposits. 2) Mechanism of formation of amyloid deposits by sysosomal enzyme digestion of immunoglobulin precursors. 3) Isolation and purification of proteolytic enzymes involved in immunoglobulin degradation.